# Sensors take chemical analysis from the lab to the field

ISSN: 0260-2288

Publication date: 1 March 1999

## Citation

(1999), "Sensors take chemical analysis from the lab to the field", Sensor Review, Vol. 19 No. 1. https://doi.org/10.1108/sr.1999.08719aaf.004

## Publisher

:

Emerald Group Publishing Limited

## Sensors take chemical analysis from the lab to the field

Sensors take chemical analysis from the lab to the field

Keywords Chemical, Fibre optic

A new hand-held sensor technology developed at the University of Washington (UW) School of Engineering will allow chemical engineers, doctors, and other scientists to perform instant, on-site chemical analysis in the field. Based on an emerging technique called surface plasmon resonance pioneered at the University, the new sensors bounce light off a sample and use the reflection of the incoming light to determine the presence and concentration of specific chemicals.

"Surface plasmon resonance sensors have been used for approximately 15 years in research labs, but the technology was too complicated, cumbersome, and expensive for other applications", explains Sinclair Yee, Professor of Electrical Engineering and principal investigator on the project. "The potential benefits for using these sensors in areas such as medicine, environmental monitoring, and manufacturing are tremendous, so we set out to develop an instrument that is portable and inexpensive."

The technology shrinks the size of a surface plasmon resonance sensor from that of a console television set to a laptop computer, and reduces the cost from $200,000 to less than$2,000. The UW probe contains a glass fibre core less than 0.5mm in diameter. White light is transmitted down the fibre core to the tip of the probe where the sensor surface is in contact with the fluid sample. The colour, or wavelength, at which most of the light is absorbed into the sample rather than reflected back up the probe is called the wavelength of resonance and depends on the chemical composition of the sample. Computer analysis of the reflected light can determine the presence and concentration of specific chemicals.

The systems are sensitive enough to detect lead, arsenic, and copper in concentrations as small as ten parts per billion, making it suitable for monitoring soil and water pollution. They may also be used for real-time monitoring of chemicals, micro-organisms, or viruses in marine environments.

For further information contact Sinclair Yee. Tel: 206/543 2894 or Clement Furlong, Tel: 206/543 1193.